Laminated distributor brush



P 20, 1966 J. DE BOO ETAL 3,274,368

LAMINATED DISTRIBUTOR BRUSH Filed Dec. 29, 1964 FIG. 5

FIG. 6

INVENTORS JEROME L. DEBOO GEOFFREY B. LUTZ TTWU r 36 ATTORNE UnitedStates Patent Ofihce 3,274,368 Patented Sept. 20, 1966 3,274,368LAMINATED DESTRIBUTOR BRUSH Jerome L. De B00, Earrington, and GeoflreyB. Lutz,

Evanston, lll., assignors to Teletype Corporation, Skokie, Ill., acorporation of Delaware Filed Dec. 29, 1964, Ser. No. 421,877 8 Claims.(Cl. 200-165) This invention relates to a distributor brush and a methodof making it and more particularly to a distributor brush for use with atelegraph distributor and a method of making telegraph distributorbrushes which assures that the resulting brushes will have certainhighly desirable characteristics.

In the telegraph industry distributors are used to serialize telegraphsignals onto telegraph lines. One type of distributor which has beenused for this purpose is the commutator type wherein the segments of asegmented commutator ring are individually connected to the outputs of atelegraph transmitter and wherein a continuous commutator ring isconnected to the telegraph line. Electrically connected distributorbrushes simultaneously pass over the two rings thereby electricallyconnecting the ring segments to the continuous ring in step-bystepfashion and thus serially impressing the output of the transmitter ontothe telegraph line. In order that the signals so serialized may be ofoptimum quality it is necessary that the distributor brush which travelsover the segmented ring come into and go out of contact with thesegments quickly and positively and that it does not make contact withtwo of the segments at once.

Accordingly, an object of this invention is to improve telegraphiccommunications by improving the distribution of telegraph signals.

Another object of this invention is to provide an improved telegraphdistributor.

A further object of this invention is to provide a distributor brushwhich quickly and positively comes into and goes out of contact with thesegments of a segmented commutator ring.

Another object of this invention is to provide a method of makingdistributor brushes which assures that they will quickly and positivelycome into contact with the segments of a segmented commutator ring.

According to the preferred embodiment of this invention a distributorbrush is provided which is comprised of two superposed, flat layers ofgenerally L-shaped Wires. The layers are mounted in a block ofinsulating material which is molded around the wires near the ends oftheir long sides. When in use the free ends of the wires are urged intoengagement with the commutator ring of a telegraph distributor withsufficient force to cause the wires of one of the layers to mergesubstantially alternately with the wires of the other layer therebypresenting a single row of wires to the commutator ring. This assuresthat all the wires of the brush will come into and go out of contact atthe same time. One method of making this type of brush is to form aplurality of straight wires into two superposed layers, mold aninsulating material around one end of the layers, clamp the free ends ofthe wires into a single row, bend the wires into an L-shape and trim thewires while still clamped so that the free ends of the wires in the rowform a straight line. This assures that when it is used the brush willpresent a single row of wires to a commutator ring.

A more thorough understanding of the present invention may be had byreferring to the following detailed description when taken inconjunction with the drawings wherein:

FIG. 1 is a front view of a telegraph distributor employing the brush ofthe present invention;

FIG. 2 is an enlarged side view of such a brush;

FIG. 3 is an enlarged top view ofsuch a brush taken from the line 33 inFIG. 2 in the direction of the arrows;

FIG. 4 is a sectional view taken substantially along the line 4-4 inFIG. 2 in the direction of the arrows;

FIG. 5 is a first step in a method of making the brush of the presentinvention;

FIG. 6 is a second step, and

FIG. 7 is a third step.

Referring now to the drawings wherein like reference numerals designatelike parts throughout the several views, with particular reference beinghad to FIG. 1, there may be seen a distributor face 11 upon which aremounted a segmented commutator ring 12 and a continuous commutator ring13. A shaft 14 extends through the distributor face 11 and is rotatablymounted with respect thereto. Secured on the shaft 14 by means of acollar (not shown) and a snap ring 15 is a rotor 16. Mounted in therotor 16 are a segment ring brush 20 and a continuous ring brush 21.These brushes are electrically connected by means of a bus 22.

As is usual in automatic telegraph apparatus the segmented ring 12 isdivided into a plurality of segments including a start segment 25, aplurality of character segments 26, and a stop segment 27. A pluralityof connectors, each of which are individually electrically connected toone of the segments, are provided, this plurality of connectorsincluding a start segment connector 28, a plurality of character segmentconnectors 29, and a stop segment connector 30. The continuous ring 13is electrically connected by means of a Web 31 to the start segment 25and, therefore, to the start connector 28.

In use, the start connector 28 is attached to a telegraph line overwhich characters are to be sent in serial fashion. The characterconnectors 29 are individually connected to the outputs of a telegraphtransmitter. This transmitter may be of any of the well known types,including punched paper tape readers and keyboard transmitters. Theoutput of these transmitters is typically parallel in nature, that is,all of the bits of the signal are sent over a plurality of wires to thedistributor at the same time. The stop segment connector 30 is normallyconnectedto a current source.

The usual practice in the telegraph industry is to transmit overtelegraph lines signals in the form of a Baudot or start-stop code. Inthis code a current is applied to the telegraph line when signals arenot being sent. This condition is known as a marking condition. When asi nal is sent the first bit applied to the telegraph line is known as astart bit and this is a spacing or no-current bit. After the start bit,a plurality of character bits may be transmitted which convey to areceiving apparatus the desired character. Finally, a stop bit which isa marking or current bit is sent. This informs the receiving stationthat the character has been completed.

In the present device as the shaft 14 is rotated by a motor (not shown)the rotor 16 rotates with it, thus driving the segment ring brush 20 andthe continuous ring brush 21 simultaneously around the segmented ring 12and the continuous ring 13. This causes the segment ring brush 20 tocome into electrical connection with the start segment 25, the charactersegments 26, and the stop segment 27 of the segment ring 12 instep-by-step fashion. Since the segment ring brush 20 is electricallyconnected to the continuous brush 21 by the bus 22 and continuous ring13 is connected to the telegraph line, this operation puts the varioussegments of the segmented ring 12 into an electrical connection with thetelegraph line in step-bystep fashion. The first segment connected bythe segment ring brush 20 in its progress around the segmented ring 12is the start segment 25. Since this segment is connected by the web 31to the continuous ring 13 and by the connector 28 to the telegraph linethere will be no current available for application to the telegraph lineat this time. Thus, a spacing bit will be applied to the line in theusual telegraph fashion. The speed of rotation of the shaft 14, togetherwith the amount of the ring 12 devoted to the segment 25, determine thelength of the start pulse. After the brush 20 has left the start segment25 it will come into contact in step-by-step fashion with each of thecharacter segments 26. An equal portion of the ring 12 is devoted toeach of these character segments so that the amount of time each of themis connected to the telegraph line is the same. Since each of thesegments 26 is individually connected by a connector 29 to an output ofa telegraph transmitter, current may or may not be available forapplication to the telegraph line at each of the segments 26 dependingupon the output of the telegraph transmitter. Each possible character tobe transmitted with apply current or no current to a differentpermutation combination of the segments 26 and thus as the brush 20traverses the character segments 26 various combinations of marking andspacing bits, representing various characters, will be applied to thetelegraph line. After having traversed all of the segments 26 and brush20 will engage the stop segment 27. Since a current is always applied tothe stop segment 27 by means of the connector 30, the brush 20 willapply current to the continuous ring 13 and, therefore, to the telegraphline when the brush is in engagement with the stop segment 27.Typically, the shaft 14 is connected to its driving motor (not shown) bya clutch (not shown). If a character is to be sent immediately after thesending of a previous character is terminated, this .clutch remains inengagement and shaft 14 continues rotation. However, if no character isto be sent after the sending of a previous character is terminated, theclutch is disengaged and the brush 20 comes to rest on the stop segment27. Thus, when no characters are being sent by the distributor a markingor current condition remains on the telegraph line.

From the foregoing description it may be understood that the quality ofthe signal which is serialized onto the telegraph line by thedistributor is dependent upon the quality of the electrical contact madebetween the segments of the segmented ring 12 and the segment brush 20.In recent years the speed at which characters are serialized ontotelegraph lines has increased from 6.5 characters per second tocharacters per second. At the same time the characters have come to becomprised of eight bits rather than five bits. The combination of thesefactors have resulted in the time duration of the bits being materiallyreduced. Consequently, it is imperative to assure that the marking orspacing condition of each of the bits is fully recognized throughout thetime duration of the bit.

In accomplishing this end it is desirable that the brush which engagesthe segments of the segmented ring 12 not be in contact with two of thesegments at once. This assures that if one of the segments is in markingcondition and the other is in a spacing condition then it will not bepossible for the brush to apply the marking condition of the firstsegment to the line while it is in partial engagement with the secondsegment. It is also desirable to have all of the wires which comprisethe segment brush engage and disengage an individual segment at the sametime. This assures that the entire current carrying capacity of thebrush is available throughout the period in which the brush is engagedwith the segment. Finally, it is desirable that the brush not bouncewhen it initially comes into contact with a segment, which may lie in aplane which is either raised from or lowered below the plane of thedistributor face 11. All of these characteristics aid in assuring thatthe segment brush 20 will be in complete electrical contact and Will befully capable of conducting a current from the segment to the telegraphline during the entire time that the brush is positioned above thesegment.

As may be best seen in FIGS. 2, 3, and 4 the brushes 2t) and 21 arecomprised of two layers of generally L- shaped wires. These layers areheld in superposed relation one to the other by the rotor 16 and, as isseen in the dotted line drawing in FIG. 2, when the brush is not usedthe layers maintain their separate character throughout the length ofthe brush. As may be seen in the solid line portion of FIG. 2 and inFIG. 3 when the brush is held in contact with the distributor face 11 bythe snap ring 15, the wires of one of the layers merge substantiallyalternately with the wires of the other layer so that the brushespresent a single straight row of wires to the distributor face 11. In somerging the free ends of the brushes 20 and 21 fan out so that thesingle straight row of wires which is in contact with the distributorface 11 has a width approximately double the width of one of the layerswhen the brush is in an unloaded condition. The single straight row ofwires of the brush causes it to have a minimum width in the longitudinaldirection. This allows an absolute minimum separation between thesegments of the segmented ring 12 and also allows all of the wires ofthe brushes to come into and to go out of electrical contact with thesegments at virtually the same time. Since the layers of Wires aremerged alternately one with the other the brush has a substantial amountof interwire friction which prevents the wires from bouncing anysubstantial amount when they are brought into contact with a segment.

The brushes are formed so that when they are in use their free endsengage the distributor face 11 on a line which lies in a plane whichextends through the axis of the shaft 14 and which is perpendicular tothe plane of the distributor face 11. In order to assure that thebrushes will have the proper dimensions and that they will fan out intoa single straight row when in use, they must be manufactured in a veryprecise and accurate manner. To this end the method of making thebrushes which is schematically illustrated in FIGS. 5, 6, and 7 may beused.

As shown in FIG. 5 a plurality of wires have been arranged in twosuperposed layers and the ends of the wires have been molded into rotor16. After the molding operation is completed, the layers of wires arebrought into contact with an upper surface 35 of a block 36 and agripping ram 37 is lowered thus gripping the wires between the ram 37and the surface 35. This gripping action causes the free ends of thelayers of Wire to merge into a single row of wires. After the wires aregripped by the ram 37 a bending ram 38 is lowered. This bending ram 38cooperates with the block 36 to form the wires into a generally L-shapedconfiguration. The bending ram 38 is so constructed that it cooperateswith the blocking ram 37 to rigidly grip the free ends of the wiresafter the bending operation is complete. At this time a knife 39 is usedto trim the free ends of the wires to the proper length thus assuringthat when the brush is in use the wires not only will have the properdimensional characteristics, but that the wires will properly fan out topresent a single straight row of wires to the distributor face 11. Afterthe trimming operation is complete, the rams 37 and 38 and the knife 39are removed thus allowing the brush to resume the shape shown in thedotted line portion of FIG. 2.

Although particular embodiments of the invention are shown in drawingsand described in the foregoing specification, it will be understood thatthe invention is not limited to these specific embodiments, but iscapable of modification and re-arrangement, and substitution of partsand elements without departing from the scope of the invention.

What is claimed is:

1. The combination with a plurality of brush contacting surfaces, of adistributor brush comprising:

a first layer of generally L-shaped, resilient wires positioned adjacenteach other in a substantially straight row;

a second layer of generally L-shaped, resilient wires positionedadjacent each other in a substantially straight row, and

means holding the layers in a position where they bear upon thecontacting surfaces with sufficient force to flex all of the wires ofboth layers and to merge the two layers into a single row of wires.

2. The combination with a brush contacting surface, of

a brush assemblage comprising:

a first row of resilient wires of a first positioned in alignment onewith another;

a second row of resilient wires of a second length positioned inalignment one with another;

means for holding the first row and the second row in superposedrelation one to the other, and

means holding the two rows against the contacting surface withsufficient force to cause the two rows to merge into a single row.

3. The combination of a distributor and a distributor brush comprising:

a first plurality of generally L-shaped wires positioned adjacent eachother in a substantially straight row extending normal to the axis ofthe wires;

a second plurality of generally L-shaped wires positioned adjacent eachother in a substatnially straight row extending normal to the axis ofthe wires;

means holding the second plurality of wires in grooves for-med betweenthe first plurality of wires; and

means urging all of the wires of the first plurality and all of thewires of the second plurality simultaneously into engagement with thedistributor to force the wires of the second plurality to merge with theWires of the first plurality thereby causing the distributor brush topresent a single, straight row of wires to the distributor.

4. The combination of a telegraph distributor and a brush for itincluding:

a flat, commutator type distributor face;

a rotor for circular movement with respect to the distributor face;

a distributor brush comprised of two superposed layers of generallyL-shaped flexible wires, and

means attached to the rotor holding the brush against the distributorface with sufficient force to cause the wires of the brush to flex andform at their free ends a single straight row of wires.

5. The combination of a telegraph distributor and a distributor brushincluding:

a distributor face having a segmented commutator ring,

a rotor for rotational movement with respect to the distributor face;

a distributor brush comprised of two superposed layers of flexible,generally L-shaped wires for electrical contact with the segmented ringof the distributor face, and

means attached to the rotor urging the distributor brush into engagementwith the segmented ring of the distributor tace with sufiicient force tocause the wires of one layer of the brush to merge substantiallyalternately with the wires of the other layer of the brush therebycausing the distributor brush to present a single, straight row of wiresto the segmented ring of the distributor face.

6. The combination of a telegraph distributor and a distributor brushincluding:

a distributor face comprised of an outer segmented commutator ring andan inner, continuous commutator ring;

a rotor for rotational movement with respect to the distributor face;

a first distributor brush for electrical contact with the inner ring ofthe distributor face;

a second distributor brush comprised of two superposed layers offlexible, generally L-shaped wires for electrical contact with the outerring of the distributor face;

means electrically connecting the first and the second distributorbrushes; and

means attached to the rotor urging the second distributor brush intoengagement with the outer ring of the distributor face with sufiicientforce to cause the wires of one layer of the brush to mergesubstantially alternately with the wires of the other layer of the brushthereby causing the second distributor brush to present a single,straight row of wires to the outer segmented ring of the distributorface.

7. A telegraph distributor for receiving the output of a telegraphtransmitter and -for serializing the output onto a telegraph linecomprising:

a plurality of electrically conducting segments including a plurality ofbit segments each adapted to be individually electrically connected toone of the outputs of the transmitter;

an electrically conducting commutator ring adapted to be connected tothe telegraph line;

an electrically conducting commutator brush in substantially constantengagement with the commutator ring;

an electrically conducting segment brush which presents a single,straight row of wires to the conducting segrnents;

an electrical connection between the two brushes, and

a rotor bringing the segment brush into electrical connection with thesegments in succession thus serially connecting the segments to thecommutator and therefore to the telegraph line, the single row, straightline character of the segment brush assuring that the entire segmentbrush will come into contact with the individual segments at the sametime.

-8. A telegraph distributor for receiving the output of a telegraphtransmitter and for serializing the output onto a telegraph linecomprising:

a plurality of electrically conducting segments circularly positionedaround a fixed point and consisting of a plurality of bit segments eachadapted to be individually electrically connected to one of the outputsof the transmitter, a start segment and a stop segment;

an electrically conducting commutator ring adapted to be connected tothe telegraph line and circularly disposed about the fixed point;

an electrically conducting commutator brush in substantially constantengagement with the commutator ring;

an electrically conducting segment brush which presents a single,straight row of wires to the conducting segments;

an electrical connection connecting the two brushes;

a rotor which rotates about the fixed point and which '2' supports thetwo brushes in engagement, respectively, with the segments andcommutator ring thereby brin ing the segment brush into electricalconnection with the segments in sequence thus serially connecting thesegments to the commutator and therefore to the telegraph line, thesingle row, straight line character of the segment brush assuring thatthe entire segment brush will come into contact with the individualsegments at the same time, and means rotating the rotor.

References Cited by the Examiner UNITED STATES PATENTS ROBERT K.SOHAEFER, Primary Examiner.

10 H. O. JONES, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,274,368 September 20, 1966 Jerome L. De Boo et a1.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 3, line 35, for "with" read will line 41, f0 "and" read thecolumn 5, line 30, after "first" insert length line 45, for,"substantnially" read substantially column 6, line 22, after "means"insert for (SEAL) EDWARD J. BRENNER Commissioner of Patents ERNEST W.SW'IDER Attesting Officer

1. THE COMBINATION WITH A PLURALTIY OF BRUSH CONTACTING SURFACES, OF ADISTRIBUTOR BRUSH COMPRISING: A FIRST LAYER OF GENERALLY L-SHAPED,RESILIENT WIRES POSITIONED ADJACENT EACH OTHER IN A SUBSTANTIALLYSTRAIGHT ROW; A SECOND LAYER OF GENERALLY L-SHAPED, RESILIENT WIRESPOSITIONED ADJACENT EACH OTHER IN A SUBSTANTIALLY STRAIGHT ROW, ANDMEANS HOLDING THE LAYERS IN A POSITION WHERE THEY BEAR UPON THECONTACTING SURFACES WITH SUFFICIENT FORCE TO FLEX ALL OF THE WIRES OFBOTH LAYERS AND TO MERGE THE TWO LAYERS INTO A SINGLE ROW OF WIRES.